Manufacture of incandescent lamps



(No Model.)

A. L. REINMANN.

MANUFACTURE OF INGANDESUENT LAMPS. No. 323,205; v Patented July 28,1885.

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ALBERT L. REINMANN, OF PITTSBURG, PENNSYLVANIA.

MANUFACTURE OF INCANDESCENT LAMPS.

SPECIFICATION forming part Of Letters Patent N0. 323,205, dated July 28,1885.

Application filed May 15, 1885. (No model.)

To all whom it may concern:

3e it known that I, ALBERT L. REINMANN, residing at Pittsburg, in thecounty of Allegheny and State of Pennsylvania, a citizen of the UnitedStates, have invented or discovered a certain new and useful Improvementin the Manufacture of Incandescent Lamps, of which improvement thefollowing is a specification.

In the accompanying drawings, which make part of this specification,Figure 1 is a perspective View of the apparatus employed in carrying outmy improved method of treating the bulbs in the manufacture ofincandescent lamps. three-way cook.

The appearance of incandescent lamps is frequently impaired by dirtyspots on the illner surface of the bulb. These spots are caused by thecondensation on the inner surface of the bulbs, when cooled, of thevapor carried into the bulb during the blowing necessary for the sealingof the platinum wires in the wall of the bulb. As long as the glassremains hot this vapor remains suspended in the air in the bulb, but assoon as the glass is cold the vapor condenses in the form of smallglobules or drops on the inner surface, and dust collecting on theglobules gives aspotted and stained appearance.

My invention has for its object the removal of the vapor from the bulband the substitution therefor of dry. air, thereby preventing thestaining of the bulb and the preservation of a bright clean surface; andto this end my invention consists in the improved step in the process ofmanufacturing incandescent lamps, substantially as hereinafter describedand claimed.

Underneath or in convenient proximity to the bench or table A isarranged the pipe 1, leading to any suitable exhaustpump, and from thispipe extends up through the table the branch pipe 2, provided with avertical and two lateral arms, 3, 4, and 5, and at the point of junctureof these arms and the branch pipe is located the three-way cock 6. Thearms 3 and 4 are adapted for the reception of the stems of the bulbs,and on the arm 5 is secured the vessel 7, containing chloride of calciumor other suitable moisture-absorbent, and having its bottom perforated,or being otherwise suitably constructed to permit of the free admissionof air.

After the bulb a has been blown and the Fig. 2 is a sectional view of a.

platinum wires and the carbons have been properly secured therein, andwhile the bulb is still sufficiently hot to prevent any condensation,the stem 1) is passed through a cork, 8, which is then pressed into theend of either one of the arms 3 and 4, the other arm being closed in anysuitable manner. The cock 6 is then turned so as to open connection withthe pipe 2, thereby permitting of the thorough exhaustion of the moistair from the bulb. Connection is maintained with the exhaust-pump untilthe bulb has become entirely cooled, after which the cock 6 is turned soas to cut off the exhaustpump and form connection with the arm 5,thereby permitting of the admission of air which has been perfectlydried by passing through the vessel 8, containing a moisture-absorbent.By this thorough removal of moist air or vapor and the substitutiontherefor of dry air the collection of moisture and dust in spots isentirely prevented. After the above-described treatment the bulb istransferred toa high-vacuum apparatus, and after being thoroughlyexhausted is scaled up.

If desired, the alternate exhaustion and admission of dried air may berepeated several times to insure a thorough removal of all moisture.

The arm 4 is usually employed only when very large bulbs are beingtreated, and it is desirable that they should be otherwise supportedthan by the stem, as .in this case by the table A.

I claim herein as my invention- 1. As a step in the art of manufacturingincandescent electric lamps, the removal of moist air or vapor from thelamps while in a heated condition, substantially as set forth.

2. As a step in the art of manufacturing incandescent electric lamps,the removal of the air from the lamps while in a heated con-

